Fourier transform infrared spectroscopy measurements

As it was shown by SNIFTIRS measurements (subtractively normalized interfacial Fourier transform infrared spectroscopy measurements) that adsorbed CO species exist from 0.3 V vs RHE on a Pt surface ... 

In this chapter, three methods for measuring the frequencies of the vibrations of chemical bonds between atoms in solids are discussed. Two of them, Fourier Transform Infrared Spectroscopy, FTIR, and Raman Spectroscopy, use infrared (IR) radiation as the probe. The third, High-Resolution Electron Enetgy-Loss Spectroscopy, HREELS, uses electron impact. The fourth technique. Nuclear Magnetic Resonance, NMR, is physically unrelated to the other three, involving transitions between different spin states of the atomic nucleus instead of bond vibrational states, but is included here because it provides somewhat similar information on the local bonding arrangement around an atom. 

The conformational changes which have been described so far are probably all relatively small local changes in the structure of H,K-ATPase. This has been confirmed by Mitchell et al. [101] who demonstrated by Fourier transform infrared spectroscopy that a gross change in the protein secondary structure does not occur upon a conformational change from Ei to 3. Circular dichroism measurements, however [102,103], indicated an increase in a-helical structure upon addition of ATP to H,K-ATPase in the presence of Mg and... 

The strength of the Bronsted (BAS) and Lewis (LAS) acid sites of the pure and synthesized materials was measured by Fourier transformed infrared spectroscopy (ATI Mattson FTIR) by using pyridine as a probe molecule. Spectral bands at 1545 cm 1 and 1450 cm 1 were used to indentify BAS and LAS, respectively. Quantitative determination of BAS and LAS was calculated with the coefficients reported by Emeis [5], The measurements were performed by pressing the catalyst into self supported wafers. Thereafter, the cell with the catalyst wafer was outgassed and heated to 450°C for lh. Background spectra were recorded at 100°C. Pyridine was then adsorbed onto the catalyst for 30 min followed by desorption at 250, 350 and 450°C. Spectra were recorded at 100°C in between every temperature ramp. 

Miniaturized chemical analysis systems have been developed for most macroscopic counterparts (Dittrich et al. 2006). The availability of optical fibers, light sources, and detectors in the visible UV and near-infrared (NIR) wavelengths makes it possible to integrate spectroscopic measurements in microreactors (Lobbecke et al. 2005). Fourier transform infrared spectroscopy (FTIR) is an efficient, broadly applicable... 

A Fourier transform infrared spectroscopy spectrometer consists of an infrared source, an interference modulator (usually a scanning Michelson interferometer), a sample chamber and an infrared detector. Interference signals measured at the detector are usually amplified and then digitized. A digital computer initially records and then processes the interferogram and also allows the spectral data that results to be manipulated. Permanent records of spectral data are created using a plotter or other peripheral device. 

Fourier transform infrared spectroscopy spectrometers can cover wide spectral ranges with a single scan in a relatively short scan time, thereby permitting the possibility of kinetic time-resolved measurements. 

This restilt was confimed by other groupsi2.i3, using Fourier transform infrared spectroscopy. Kunimatsu and Kita made further progress using polarization modulation to enable quantitative measurements and showed... 

Fuller, M.P. and Griffiths, P.R. (1978) Diffuse reflectance measurements by Fourier-transform infrared spectroscopy. Anal. Chem., 50 (11), 1905-1910. 

The most recent advance in VCD instrumentation has been its adaptation to Fourier transform infrared (FTIR) measurement (23-25). The details of this technique involve a new method of FTIR measurement termed double-modulation FTIR spectroscopy. Thus spectra of very high quality and resolution have been obtained using a standard VCD modulator and detector, a glower source, and a commercially available FTIR spectrometer system. In fact an entire FTIR-VCD spectrometer can be assembled from a few commercially available components. It is found that the major advantages of resolution, throughput, and... 

Fourier transform infrared spectroscopy (FTIR) s Measures protein and carbohydrate vibrational, stretching, and bending energies... 

Yokelson, R. J., R. Susott, D. E. Ward, J. Reardon, and D. W. T. Griffith, Emissions from Smoldering Combustion of Biomass Measured by Open-Path Fourier Transform Infrared Spectroscopy, . /. Geophys. Res., 102, 18865-18877 (1997). 

FTIR Fourier transform infrared spectroscopy has been used for many years to measure atmospheric gases. Because FTIR has become such a common analytical method, we do not describe the technique itself here but rather refer the reader to several excellent books and articles on the subject (e.g., see Griffiths and de Haseth, 1986 Wayne, 1987). For reviews of some atmospheric applications, see Tuazon etal. (1978,1980), Marshall et al. (1994), and Hanst and Hanst (1994). 

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